1. Field of the Invention
The present invention relates to an abrasive tape, and more particularly, it relates to an abrasive tape having an excellent and uniform polishing property over its entire length without causing scratching flaws on the surface of a polished material.
Since the abrasive tape is easy to handle, it is frequently used for polishing the surface of a material such as a flexible magnetic disk, a magnetic tape, a magnetic head, a plastic product, a mold, an optical fiber and various machine parts.
In general, these polished materials should be precision processed, and therefore scratches on their surface usually make trouble.
2. Description of the Related Art
In general, the abrasive tape comprises a flexible substrate such as a polyester film, and an abrasive layer which is formed on the flexible substrate and contains a binder resin and an abrasive grain, such as Al.sub.2 O.sub.3, Cr.sub.2 O.sub.3, SiO.sub.2 and SiC powders, and is widely used to smoothen the surface of the polished material, for example, the flexible disk and the magnetic disk by polishing minute protrusions on the surface of the polished material. (cf. Japanese Patent Koukoku Publication No. 44714/1978.)
However, since such conventional abrasive tape has a hard and tough abrasive layer, some minute protrusions of the polished surface drop in the form of pieces without being abraded and adhere to the surface of the abrasive tape, and then scratch the surface of the polished material, such as a magnetic layer. The scratches on the polished surface tend to damage the polished material completely.